Governor adjusting means



Feb. 1, 1955 R. E. FIELD 2,700,962

GOVERNOR ADJUSTING MEANS Filed Dec. 18, 1955 INVENTOR TTORNEY United States Patent GOVERNOR ADJUSTING MEANS Robert E. Field, Pontiac, Mich., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application December 18, 1953, Serial No. 399,109

Claims. (Cl. 121-194) This invention relates to engine governor installations and, more particularly, to means enabling the ad ustment of the speed setting or the governor unit thereof.

In governor installations for internal combustion engines of trucks, busses, and heavy duty craft and vehicles, the governor control unit may be located to advantage within the interior of the engine, as for example, within the engine oil pan. Such an interior location or the governor unit not only discourages unauthorized personnel from tampering with the speed setting thereof but trees or provides desirable working space that otherwise would be occupied by the governor were it located without the engine, as in prior governor installations. Particularly in the case of hydraulic governors, the interior location of the governor control unit withln the engine oil pan enables the governor to be intimately associated and cornblned with the engine lubricating oil pump in such manner as to permit the governor to be driven rrom the engine through a common drive shaft with the pump and to eliminate separate hydraulic connecting lines therebetween. Also, all the nuid carrying parts of the governor installation may be connhed within the interior of the engine, tnereoy decreasing the length of hydraulic connecting lines between the components of the speed control system and, more important, preventing loss of engine on should a rupture develop in the connecting lines, as could occur in prior governor installations where all or a part of the iluld carrying members of the system are without the engine.

where the governor control unit is located within the interior of the engine in accordance with the roregoing, there is presented the problem of providing suitable means to enable authorized personnel occasionally to check and ad ust the speed setting of the governor after it has been installed. '10 remove the oil pan on such occasions is, of course, most inconvenient and undesirable. Nor is it desirable to drain the engine oil, as would be required where the governor speed setting adjusting element is submerged oelow the level of the oil within the pan and where it is desired to run the engine during the ad ustment process.

Accordingly, the present invention has among its objects generally to provide suitable structure in governor installations of the above and a related character that enables a simple and ready adjustment of the speed setting of the governor control unit from without the engine and, specifically, without the necessity of removing the engine oil pan or draining the oil therefrom.

in accordance with the present invention the above objects are attained by provision of suitable sealing means associated with an opening located closely adjacent the adjustable element of the governor unit and in a wall of the oil pan. The seal includes a compressible elastic diaphragm having a slight break or opening in the surface thereof such as normally will be substantially self-sealing and prevent flow therethrough and which is elastically expandable to conform to the shape of an adjusting tool insertable from without the oil pan through the diaphragm and pan opening to engage the governor adjusting unit.

Figure l is a front elevation view with parts broken away and insection illustrating a governor installation within an engine oil pan that includes suitable sealing structure'in accordance with the present invention;

Figure 2 is an enlarged detail view of the sealing structure employed in Figure 1; and

Figure 3 is a bottom plan view with parts broken away taken in the direction of 3-3 of Figure 1.

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kererring to the drawings, the present invention is illustrated in an hydraulic governor installation for an engine speed controlling system and comprises, in general, an engine lubricating oil pump 10, a governor control unit 12 and a pressure responsive servo device 14, which is mounted on a wall of the engine crankcase 16 and operatively connected with the engine throttle valve 18 in the intake manifold 20 of the engine. An oil pan is shown at 22 detachably connected to the engine crankcase and forms an oil sump containing a quantity of lubricating oil which is supplied to the pump inlet through a float-type strainer 24 of conventional design.

The oil pump 10 is mounted in an opening in the engine crankcase communicating with the oil sump and may be of the commonly employed high capacity gear type. The pump comprises a generally one piece housing 26 having a detachable combination cover and governor adapter plate 28 therefor. A pump chamber 30 is formed within the lower end of the housing and has a pair of intermeshed pump gears therein, one of which is mounted on a drive shaft 32, which extends axially through pump housing and is adapted to be driven at its upper end from a gear on the cam shaft within the crankcase of the engine.

The pump cover and governor adapter plate 28 is preferably a one piece casting having an integrally formed intake conduit 34 that communicates at its upper end with the intake or low pressure side of the pump through the cover portion and at its lower end with the strainer device 24. The cover and adapter plate portion 28 is detachably connected to the pump housing, as by bolts 40, and is bored and counterbored as shown at 42 and 44 co-axially with the pump shaft. A shallow pressure pocket 46 in the high pressure region of the pump is formed in the face of the cover 26 adjacent the pump chamber.

Since the structural details of the governor control unit are not of particular importance to the present invention, only such parts of the governor externally connected in the speed control system and which co-operate with the present invention will be described. In brief, the governor control unit 12 is detachably connected to the pump cover and adapter plate 28 by bolts such as 48. The rotatable shaft 50 of the governor extends through the bored and counterbored portion of plate 28 into the pump chamber 30 and has a nib 52 formed at the end thereof which is received in a mating drive slot 54 in the pump shaft 32.

Pressure oil is supplied from the high pressure side of the pump through an axially directed passage 56 formed in the pump cover 28 and extending between the pressure pocket 46 and the inlet to the governor unit. In some governor units the pressure passage from the pump could communicate with a groove or slot formed in the pump and/or governor shaft and further connecting fluidcarrying passages could be provided in the governor shaft and lead to the inlet of the governor.

A short length of hydraulic line 58 connects the outlet of the governor to the pressure responsive servo device or slave unit 14 which may be interiorly mounted on a wall of the engine crankcase 16, as shown. The device 14 may be a conventional pressure diaphragm structure, one side of the diaphragm 60 of which forms a flexible wall for a pressure chamber Within the housing 62 of the device and is adapted to be exposed to the fluid pressure regulatably supplied thereto through the governor control unit. The other side of the diaphragm may be exposed to atmosphere and is operatively connected to the engine throttle valve 18 in the engine intake manifold 20 through suitable mechanism including an operating rod 64 and lever 66.

The governor control unit has the customarily provided adjustable regulating element 68 accessible from without the governor housing for adjusting the speed setting thereof, as by adjusting the spring tension applied to an internal pressure regulating member such as a centrifugally unbalanced control valve or other member. As shown in Figure 1, the governor speed control setting element is located close to a bottom wall 70 of the engine oil pan 22 and is submerged below the oil level therein.

In accordance with the present invention the adjustable 3. element 68 may be adjusted from the exterior of the engine without necessitating removal of the engine oil pan or draining the oil therefrom by the seal and plug arrangement best shown in Figure 2. The bottom Wall 70 of the oil pan is struck upwardly to form a shallow circular indentation 72 in the vicinity of the adjustable element 68 so as to decrease the spacing therebetween and an off-center opening 74 is provided in the indentation immediately below the governor adjustable element. A short cylindrical flanged guide member 76 centered with and surrounding the indentation is welded to the bottom of the pan, as shown.

Centered with and extending downwardly from the pan opening 74 is a short cylindrical, internally threaded collar member 78 brazed to the oil pan and providing an oil tight joint therewith. The inner diameter of the collar 78 is greater than the diameter of the pan opening and receives an elastic diaphragm 80 that has a small break, slit, perforation or opening 82 therethrough. The diaphragm is firmly seated and retained against the adjacent surface of the pan indentation by a slotted externally threaded retainer ring 84 threadably received within the collar 78. A removable plug or cap 86 is threadably received in the end of the collar opposite the pan and carries an O-ring 88 on the shank thereof between the plug and the adjacent edge of the collar.

The diaphragm 80 is preferably composed of oil resistant elastic material such as Buna N rubber, and the break or opening 82 therein should be of the least possible dimension so as to tend to contract and provide some selfsealing action and should be so formed as to prevent tearing thereof. The retainer ring 84 may be adjusted tightly against the under side of the diaphragm so as to compress the diaphragm and further cause the opening 82 therein to contract and seal against flow of oil therethrough. The sealing action is further aided by the surface tension of the oil so that negligible leakage will be had through the perforation in the diaphragm, and any slight leakage therethrough will be collected in the space above the plug 86.

In order to adjust the governor element 68, the plug 86 is removed, and an adjusting tool, such as a screw driver, wrench or the like is inserted through the openings in the collar, retainer ring, diaphragm and pan to engage and turn the adjustable element. The cross-section of the adjusting tool being larger than the perforation in the elastic diaphragm expands the perforation which forms an effective seal with the surface of the tool and prevents leakage of oil from the pan during the adjusting process. Removal of the tool permits the diaphragm opening to contract and seal the pan opening against leakage of oil therethrough, as mentioned hereinabove. After the adjusting or checking process, the plug 86 is replaced and a wire seal 92 inserted between the plug and collar, as shown.

In the claims:

1. In an hydraulic governor installation for an engine having a source of engine-developed lubricating oil pres sure, an oil sump and an engine driven hydraulic governor unit having an adjustable element for adjusting the speed setting thereof, means co-operating with an opening in a wall of said sump adjacent the said adjustable governor element permitting adjustment thereof from without the sump and sealing the opening against leakage of oil therefrom, said means including an elastic diaphragm having a perforation therein communicating with said sump wall opening, and removable plug means for said sump opening, said perforation in said diaphragm being elastically expandible to conform to the shape of an adjusting tool insertable through said perforation and said sump opening to adjust said adjustable element.

2. In an hydraulic governor installation for an engine having a source of engine-developed lubricating oil pressure, an oil sump and an engine driven hydraulic governor unit having an adjustable element for adjusting the speed setting thereof, means co-operating With an opening in a Wall of said sump adjacent the said adjustable governor element permitting adjustment thereof from without the sump and sealing the opening against leakage of oil therefrom, said means including an elastic diaphragm having a small opening therein communicating with said wall opening, retaining means seating said diaphragm against said sump Wall and compressing the diaphragm to close the opening therein, and removable plug means sealing said sump against leakage of oil from the openings in the sump wall and diaphragm, said diaphragm opening being elastically expandible to conform to the shape of an adjusting tool insertable through said diaphragm opening and said sump opening to adjust said adjustable element.

3. In an hydraulic governor installation for an engine having a source of engine-developed lubricating oil pressure, an oil sump and an engine driven hydraulic governor unit having an adjustable element for adjusting the speed setting thereof, means co-operating with an opening in a wall of said sump adjacent the said adjustable governor element permitting adjustment thereof from without the sump and sealing the opening against loss of oil therefrom, said means including a collar member secured to said sump wall and surrounding the opening therein, an oil resistant elastic diaphragm within said collar having a slight break extending therethrough and communicating with said sump wall opening, a retaining member within said collar seating said diaphragm against said sump wall and compressing the diaphragm to close the break therein, and a removable plug capping the end of said collar opposite the sump Wall and sealing the sump against leakage of oil through said sump opening and diaphragm.

4. An oil pan having an opening in the bottom wall thereof, an internally threaded collar secured to said wall and surrounding said opening therein, an elastic diaphragm having a slight opening therein communicating with said wall opening, an externally threaded lock ring received in said collar retaining said diaphragm against said wall and compressing the diaphragm to close the opening therein, and a plug threadably received in the end of said collar remote from said pan.

5. An oil pan having an opening in the bottom wall thereof, an internally threaded collar secured to said wall and surrounding said opening therein, an oil resistant elastic diaphragm having a slight opening therein communicating with said wall opening, an externally threaded lock ring received in said collar retaining said diaphragm against said wall and compressing the diaphragm to close the opening therein, and a plug threadably received in the end of said collar remote from said pan.

References Cited in the file of this patent UNITED STATES PATENTS 1,731,823 McCuen Oct. 15, 1929 1,887,998 Fageol Nov. 15, 1932 1,983,139 Lovell Dec. 4, 1934 2,157,512 Watt May 9, 1939 

